Sprinkler system alarm accelerating means



Aug. 20, 1935.

T. M. ALLAN SPRINKLER SYS TEM ALARM ACCELERATING MEANS Filed May 24, 1953 i I INVENTOR- Womas/ffl/[aaj M4 ATTORNEY- Patented Aug. 20, I935 SPRINKLER SYSTEM ALARM ACCELER- ATING MEANS Thomas M. Allan, San Francisco, Calif., assignor to American I District Telegraph Company, Jersey City, N. J., a corporation of New Jersey Application May 24, 1933, Serial No. 672,538

18 Claims.

This invention relates to sprinkler systems, and alarm means therefor and to means for preventing false alarms by water hammer surges, and

operate the alarm.

more particularly to valve operated'alarm systems; though it is noted that in some of the claims the invention is not limited to alarm systems nor in some respects even to sprinkler systems.

One object of the invention is to provide an improved system of this kindwherein water hammer surges are prevented from sending false alarms by maintainingthe pressure inside of the system high enough to prevent the opening, by water hammer,'oi an alarm operating check valve.

The invention is shown in combination with a sprinkler system conduit Comprising a lower citypressure portion, a sprinkler portion, and an intermediate expansion portion therebetween in which is disposed an alarm check valveand a city check-valve opening toward the sprinkler portion, the alarm valve being nearest the sprinkler portion and controlling an alarm sure portion into the intermediate portion between the check valve, to'prevent water hammer surges from the city pressure portion from passing to the alarm valve and giving false alarms.

The pressure in said intermediate portion and the sprinkler portion is normally the same,'and when the sprinkler; heads first open, it takes some time for the pressure in the sprinkler portion to fall below that in the citypressure portion to cause flow to open the alarm valve to I To prevent this delay is another object of the invention,- and I provide a pressure tank adapted to retain compressed air; in its upper part, and having a pressure pipe extending from its lower .part to the conduit between the valves, and serv ing for maintaining pressure and quickly expanding the fiuid volume between said check valves whena sprinkler discharges, and main such systems and to provide a simple apparatus of this kind which is economicaland reliable in operation, and economical to manufacture and install.

.Stillother objects of the invention will appear as the descriptionproceeds;v and while herein details of the invention are described in the specification and some of the claims, the invention is not limited to these, since many and various. changes may be made without departing from the scope of the invention as claimed in the broader claims.

In the accompanying drawing showing, by wayof example, several of many possible embodiments of the invention,

Fig. 1 is a fragmental side, elevation, partly in section, showing the system provided with an air pressure tank for supplying expanding-fluid pressure. for initially operating the alarm valve, two devices being shown for supplying compressed air to the tank;

, Figs. 2,and 3 are fragmental side elevations, of modifications, showing the air chambers for supplying said pressure; and

Fig. 4 is a fragmental elevation partly in section, showing another modification showing a weighted accumulator for supplyingsaid pressure.

The principal features of the system will first be briefly indicated, after which the various features will be described in detail.

My invention, very briefly stated includes a sprinkler system comprising a conduit having a city pressure portion 9, a sprinkler portion Ill, [2, and an intermediate expansion portion H therebetween in which are interposed alarm and city check-valves 20, 2| opening ,toward the sprinkler portion. An excess pressure pump 35 raises the pressure in the expansion portion H sufficiently to prevent the passage of water hammer surges to the alarm Valve 20. An air pressure reservoir communicates with said expansion portion It and is adapted, when a sprinkler discharges, to maintain pressure and quickly expand the fluid volume between said check valves a suflicient length of time to open the alarm valve and operate the alarm.

Now the invention will be described in detail.

My invention is embodied in a sprinkler system shown in combination with fioors 5, 6 and ceiling 7 of a building and comprises a conduit 9, I0, I l l2 adapted to receive water under pressure from a city main or other pressure supply and comprisinga lower city pressure portion 9, a riser portion I D, an intermediate horizontal expansion or protective portion H therebetween, andan upper horizontal distributing portion l2.

Branch pipes M, M supplied by the riser Ill and upper portion l2 have the usual sprinklerheads l5 therein; and a usual testing pipe I! joining the upper partof the ccnduithas'a gatevalve I8 therein whereby water maybe discharged for testing the system.

An alarm check-valve 2i! and a. city check-valve 2i in said intermediate 'expansion portion' H adjacent to respective hand valves 22, 23, open toward the riser portion; The alarmvalve 2D- is I nearest the riser portion Hland controls an alarm circuit 25, 26, 21 having a switch 28,;23therein controlled by a lever 30 intermediately fulcrumed in liquid-tight mannerin the casing 3 of said alarm valve and engaging the movable, valve" member 32 and here shownas'carryingtlie mov-. j

"j and lower'parts, check valves 52 and 53 opening towarduthe tank. Pressure gauges'Se, 55- comableswitch member 29 of fisaid switchsaid'lever being operated by said member 32 to close-the switch when sufficient water flows through the I alarm valve 7 I i p A hydraulic excess pressure pump 35 .having an exhaust pipe 33'and an inlet pipe3'l, is connected to the'city pressure portion: it of: the-conduit, whereby the pump is fed and driventodraw water from the portion 9, and; force it under: pressure through a pressure pipe '38. into the expansion portion H, whereby the pressureinthe system, is raised] sufi'iciently tot prevent; water hammer V surges fromthe city. pressure portion '9 from passing through the expansion portion! 1 to the alarm valve 29 to send a false alarm. With the system :as, thus far described in detail, should sprinkler headsnifi discharge, the pressure willlbe gradually lowered, thus starting the pump 35;. but there will be several minutes.

before the pressure in the system becomesa's'low as the pressure on the city side of the city valve .2 i and allows'i'low of the citywater through the intermediate portion I I into the system. Thus flow from thecity. pressure portion will not itself immediately openithe alarm' valve.--Also since 253;" and as the flow from thefpump through the j pressure pipe 38 is not suflicient'toj cause the alarm .valve member-32 to operate -the alarm, there isa need for some additional means to the system, as so far described, to open the alarm valvesubstantially as soon as the sprinklers open, sothat the alarm will not be delayed'ior the several minutes until there is full flow from the city pressure portion 9. I To meet this need; I provide a means for mainand'2 lwhen sprinkler'heads discharge, and main tainihg said pressure and continuing the expansion during initial discharge 'sufficiently long to open the alarm valve and operate the alarm.- Said. expanding means comprises anair pressure: tank. orchamber ac adapted to retain com pressed air in its upper i part at a pressure equal to that in the expansion portion H and havilnga drain valve 4 l, 'anda pressure pipe 42 extending from its loweripart to the interior of the alarm I valve casing.3l at thesideof the member'32 toward the expansion portion .1 l. 'Ihe' pipe 42 is provided with agate vva1ve 43 and'a stopcock 44,

veniencepm H v When sprinkler heads 'open,-pressure-in the the latter being nearer the alarm valve'ffor. con

' conduit portions l1] and 12* immediately lowers;

and the pressure in the portion l tends to lower, but is maintained by upward flow of water through the pipe. 42, thus effecting a difierence in pressures on both'sides of the valve member 32.

The'thus maintained higher pressure in the portion i causes flow from portion l I into the riser, thus opening the valve member 32, closing the switch 28, 29 and operating the alarm.

Means are provided forsupplying compressed air to the upper part of said tank id. This means may comprise a small air compressor 55 discharging into -the-tank, or may'oomprise a small an intermediate gate valve 5!, and at its upper item, thereby to ,compressthe" air in the tank,; as

' will now be explained;

To compressthe air 'in thetank' it: byrrneans of the pipe 4'], itis necessary to-iclosethevalve 23 and drain :the system. and the tank .59. The operator then closes valves ii, 23 and M and openst valve 5 I Water .is then admitted to} the system by opening control va1ve'23. As the water flows into. the system, it forces the air upwarde lyand out-through the pipe 4'? connecting to the highestpoint 39 inthe sprinkler system. 'From there the air passes through check valves 53 into the tank 40. When the system has. been thusfilled,.the, valves 43 and M areopened, thus supplying the tank'with water at-thesame pressure 'carried'in the portion! 8 between the alarm check valve 20 and thecity check valveil, The valve 5! may then be tightlyclosed to prevent leakage 'Qf r s ure a k th ls the h k alv fl i th sy lf now a sprinkler head [6 opens, the -pressure shown by the pressure gauge 60 will be reduced slightly and the accumulated pressurein the tank 40 will servetoalmost instantly open the alarm check valve member 32 and thus operate the wa- Pressure gauges'54, 5 5, 56 and show the pressures in various partsi'of the. systemiby" which the condition" of "the system can be ascertained. Instead of meanssuc'h as the tank ed and pipe 42," I may provide an'air-chamber it) 'on' topof and communicating with'the pipe Ii, as in Fig. 2. To prime the air chamber, as in'Fig. 2, withcorn pressed 'air,-'the system may be drained; or the, valves 22 and 23 maybe'closed and-only theconduit portion l 1*drainedfthrough the drain valve it, thus draining the air chamber. Then water is turnedinto. the system, or into thepipe it,

thus compressing air into the airichamber .482,

.The airjchamber 40' may befilled withvcorn- Pumps i5,fi5fmay be manually controlled, or

' they may berautomatically controlled by the circuit 62,63, 6% "controlled by the pressure switch 64 controlled by pressure in the'tank or chamber.

QIn'the'f rm of invention of Fig. 4,--the elastic force for supplying the pressure to *the conduit initially :forced ,therein' by, the city pressure and l excess pressurepumpdrives the air fromthe sysportion i ll comprises a weighted plunger 65 slid able in a packing 66 at the upper end of a -pipe 61 communicating with the conduit-portion H. This ;p1unger;65 carries, at its upper 'end,-"'a table 68 on which are placed weights 69; These weights are sufiicient tobalance the pressure in the system; and when in the position shown, theyvprovide pressure sufficiently great, and suificiently continued during discharge, to operate the valve 32 and switch member 29.

- I claim as my invention:

l. A fire extinguishing system comprising a conduit having a water supply portion, a normally closed discharge portion, and an intermediate portion; a check valve separating the discharge portion from'the intermediate portion, said valve opening in the direction of water flow to'the'discharge portion; alarm means'op'erable bys'aid water flow; means to establish a pressure higher than supply pressure in the intermediate portion normally and during the initial opening of a sprinkler head, said check valve and the intermediate portion constituting the only means of supplying water to the discharge portion when the discharge portion is opened. i

" 2; A fire extinguishing system comprising 'a conduit having a water supply portioma normally closed discharge portion, and an intermediate portion; a check valve separating the supply portion from the intermediate portion; a second check valve separating the intermediate portion from the discharge portion; both of said valves opening in the direction of flow to the discharge portion; alarm means operable by water flow from the intermediate portion to the discharge portion, means to establish a pressure higher than supply pressure in the'conduit beyond the'first mentioned check valve to'thereby prevent operation of the alarm due to an increase in pressure in the supply line resulting from a water hammer; means to maintain said higher pressure in said 7 intermediate portion to effect a diirerence in pressure on the oppositesides of said second valve and cause sufficient flow to operate said valve upon the initial opening of the discharge portion; the second mentioned check valve and theintermediate portion constituting the only means of supplying water to the discharge portion when the discharge portion is opened. i I

3. A fire extinguishing system comprising a conduit having a water supply portion, a discharge portion including normally closed sprinkller heads operable by fire conditions, and an intermediate portion; a check valve separating the su ply portion from the intermediate portion; a second check valve separating the intermediate portion from the discharge portion; both'of said valves opening in the direction of flow to the discharge portion; alarm' means operable by flow to the discharge portion'whenthe second valve is opened by such flow; means to establish a. pressure higher than supply pressure in the conduit beyond the first mentionedcheck valve to thereby prevent operationv of the alarm due to an increase in pressure in the supply line resulting from a water hammer; means for supplying .additional water to said intermediate portionat said higher pressure in order to maintain said higher pressure in said intermediate portion to efiect a dinerence in pressure on the opposite sides of said second valve'and cause sufiicient flow to' operate said .valve upon the initial opening of a sprinkler head; the second mentionedcheck valve and the intermediate portion constituting the only means of supplying water to the discharge portion when the discharge portion is opened.

I 4. A fire extinguishing system comprising a conduit having a'water supply portion, a discharge portion iincluding normally closed sprinkler heads operable by fire conditions, and an'intermediate portion; a check valve separating the supply portion from the intermediate portion; an alarm operating check valve separating the intermediate portionfrom the discharge portion; both of said valves opening in the direction of flow to the discharge portion; alarm means operable by said alarm operating valve on its being opened by flow to the discharge portion, means to establish a pressure higher than supply pressure in the conduitbeyond the first mentioned check valve to thereby prevent operation of the alarm due-to an increase in pressure in the supply line resulting from a water hammer, means for supplying additional water to said intermediate portion at said higher pressure in order to maintain said higher pressure in said intermediate portion to effect a difference in pressure on the opposite sides of said alarm operating valve and cause sufficient flow to operate said valve upon theinitial opening of a sprinkler head; the sec-' ond mentioned check valve and the intermediate portion constituting the only means of supplying water to the discharge portion when the discharge portion isopened. -5. A fire extinguishing system having a'water supply portion subject to water-hammer, a normally closed discharge portion andan intermediate portion; a check valve separating the supply portion from the intermediate portion; a second check valve separating the intermediate portion from the discharge portion; both valves opening toward the discharge portion; alarm means operated by said second valve during flow toward the dischargemeans; and means for maintaining pressure in the intermediateportion greater than that in the discharge and supply portions during initial discharge from the dis charge portion; the second mentioned check valve and the intermediate portion constituting the only -means of supplying Water to the discharge portionwhen the discharge portion is opened.

6. :A sprinkler system comprising a conduit having a supply portion, a normally closedidischarge portion, and an intermediate portion therebetween constituting the only normal liqhid-conducting communication betweenthe supply and discharge portions; a checkvalve in said intermediate portion opening toward the discharge portion; an alarm operating means operated by flow from said valve to the discharge portion; means for raising the pressure in the intermediate portion above the pressure in the supply portion; and means communicating with said conduit between said valve and operating means for maintaining pressure in the conduit and adapted, during and after initial discharge,

to causeyieldable pressure on the fluid between,

-termediate portion, bothopening toward the riser portion, the; alarm; valve being nearest the riser portion; anjtalarrn means controllediby the alarm valve; pump means :for f orcing: waterlin- ,der pressure from-othe 'cityr pressure portionqinto the intermediate portions to raise; the: pressure p in. the expansion po'rtionvabove the pressure in theicity pressure portion, to prevent water ham:

.mer. surges from} the city; pressure portion; from passing the intermediate :portion to. the alarm valve a: pressure :tank adapted to, retain ;-c.om pressed air infita upper part, and havinga pressure pipelextendingwfromdts lower part to the intermediate; portion; a pipe; extending iirom an r upper part "ofhthersystemto; the pressure tank and having a normally .cIQsedgate valve therein; and. a check valve in, said pipe-gopening-toward .the tank'.

8. Incombination; conduit comprisingasiipr ply; portion;v a normallyucloseddischarge, portion, and an ,inteflnediate portion therebetween; a vehecklvalve inisaid intermediate portion opening toward-the discharge portion; afiuid-flow-om erated translator operating means between said valve and the idischarger portion; anair pressure chamber having its bottom part communicating 'withrsaid .conduitibetween said ,valve and operating means and means ior supplying =compressed air from the exterior of; the conduit directly into the air-pressure'chamber fyfl 9. A sprinkler-system; comprising. 'ag conduit comprising a pressure portion: subject. to water-v I hammer,and;a;sprinkler portion; apheck-valve sure portion drives theaair. from1the system' throughsaid pipe,"thereby to compres'suthe'air ,7

between said portions; opening. :toward the sprinkler portion; and; pump means operated by water" irom the pressure -portiong-at normal pressure during absence of waterfhammer, for forcing ;-water under r pressurefrom the pressure portion into -,the sprinkleportion to ;.raise ;-the pressure in the sprinkleportion above-that in the pl'essure portion to prevent; water; hammer surgesjirom the citypressure portion from opening the alarm valve. r

.',10.,A sprinklerisystem"comprisingi a i comprising a pressure portion, a'normallyjclosed' "discharge .portionghand an, intermediateportion therebetween; check-valves in said intermediate portion opening toward the discharge portion-s. an alarm 1. operated by the valve remote i from the pressure-portion; anair pressure tank having its lower part communicating with said intermediate portion; and means for supplying compressed air to'the upper partpi said. tanki: Said means comprising a; small air; pipe extending from an upperor the:highestpart of thesystem to-thezlower part of the pressure tank and having therein annintermediate-gate valve, and have ing, at itsupper and lower parts eheck valves opening, toward the tank, andralso having press sure gagesiadjacent to and on bothjsides: ofthe upper check; valve; said-air, pipe [servingnto conduct air to the tank from'thepreviously empty system, when water forced therein from-thepresinthe tank. 1 I 11. In compinatioma; conduitwcomprising a supply portion, a; discharge portion adapted to be closed, and an intermediateportionthereber tween a'check valvein said intermediate portion opening :toward the discharge portion; a translator. operating means operated-by flow 1etwee1i I said valve and the discharge portion; means for raising the pressure in the intermediate ,;portion above that in the supply portion, a t-piston -chamber communicating;with;saidi conduit ibetweengoiipos a val e. a d e fins. ans; a'pi o in the chamber; and "means; for; maintaining pressure on the,piston; v i

. 12- .1A. r .kl r"sy t m;ccm i e a n u havin asnjn y orti a, a llv o d charge portion, and an intermediate portion 'therebetween,eonstituting the only normal liquid- K conducting [communication between the supply and discharge portionfiia check valve in said intermediate portion opening toward the discharge portion; an alarm operatingneans operated by now. from said valve to the discharge portion; means for raising the pressure inthe intermediate portion above the ;.pressure inthe supply portion comprising a piston chamber communh catingwith said condnit between said valve and operating means; a piston in the chamber; and pressure ,means for maintaining pressure on the piston.

,v v 13. y A. sprinkler 1 system comprising a conduit v c m i s a Pre u i m ije t to W hammer, and a. sprinkler portion; a check-valve between said portions opening toward the sprinkler portion and means controlledby the pressure in the pressure p'ortion for; automatically e s er es t e r s am he'sp i k portion apbyethe'pressure in the pressure, portion in ac: cordance with'the latter pressure.

ing asupply' perso a normally closed discharge portion, and an intermediate portion therebetween; a check valve. in said intermediate portion opening towarol the discharge portion; a water- 'flow-operatedtranslator'fop'erating means betWeeni s aidvalve andiithe v'dischaige portion; an

airfpre'sjsure' chamber having its bottom part connnunic'ating with said conduit .betweensaid valve andcperatingt means; and means for re-' placing'jair absorbed'ircim the chamb-er 'by water and for supplying coinpressedairfiinto the air;-

pressure chamber while forcing water therefr -E U v t 15. A sprinkler system comprising, a water conduit'comprising fa pr'essureportionand'a' normally closed dischargeportion'; a Y check-valve between said portions opening towardgthe' discharge por- 14.,In combinatio' a water conduit compris tion; an alarmmeans operatedby water flow to the-discharge portion;-an"-air pressure tank; means 'for establishing communication between the tank and the conduitgon-the discharge side of the valvej' an air 'pipe extendin'gfrom an upperpart of'the system to the pressure tank and the valve; pipe extending from an upper part'of the system 'tothe' lower part of the pressure 1 tank '1 and having; a'xvalve interposed there in; saidqairipipe. serving toconduct air to the tank iromv the l previouslyempty: air-filled system, when water-forced into the system from the pressure portion drives the air. from the system through said air pipe, into the tank, whereby additional air is forced into the tank and compressed therein, thereby increasing the'weight of air in the tank above that originallyv in the tank when the; system? was empty, ithereby increasing vthe capacityof; the tank;without increasing the size and, cost of the tank, thereby, deferring the. ex-.-.

haustion of air in the tank from absorption by the water," thereby saving frequent refilling with air and permitting ,a smaller and cheaper tank than. would be otherwise possible.

17. A sprinkler system comprising, a water conduit comprising a pressure portion, a normally closed, discharge portion, and an intermediate portion therebetween; check-valves in said intermediate portion opening toward the discharge portion; an alarm operated by water flow to the discharge portion; an air pressure tank having its lower part communicating with said intermediate portion between said valves; and means for supplying compressed air to the upper part of said tank; said means comprising a small air pipe extending from an upper or the highest part of the system to the lower part of the pressure tank and having a valve interposed therein. 7

18. A sprinkler system comprising, a Water conduit comprisinga pressure portion, a normally closed discharge portion, and an intermediate portion therebetween; check-valves in said intermediate portion opening toward the discharge portion; an alarm operated by water flow to the discharge portion; an air pressure tank; a valved pipe connecting the lower part of the tank with said intermediate portion between said valves; a small air pipe extending from an upper or high part of the system to the pressure tank and having a valve interposed therein; said air pipe serving to conduct air to the tank from the previously empty air-filled system, when water forced into the system from the pressure portion drives the air from the system through said pipe, into the tank, whereby additional air is forced into the tank and compressed therein, thereby increasing the weight of air in the tank above that originally in the tank when the system was empty, thereby increasing the capacity of the tank, without increasing the size and cost of the tank, thereby deferring the exhaustion of air in the tank from absorption by the water.

THOMAS M. ALLAN. 

